Hinge last



May 8, 1928. I 1,668,611

' w. W.ISLACK HINGE LAST Filed Oct. 24, 1922 Patented May 8, 1928.

uni-TED STA PATENT-OFFICE XVALTER W. SLACK, OF SPRINGFIELD, VERMONT, ASSIGNOR T0 FITZ-EMPIRE DOUBLE h PIVOT LASTCOMPANY, OFAUBURN, MAINE, A CORPORATION OF HINGE LAST.

This invention relates to collapsible lasts, and is disclosed in its application toan 1mpositive lock last, that is, a last wh ch can be collapsed by pressure alone but wh ch ofiers to collapse a definite and increasing resistance over a short distance from the extended position. Lasts of this type require some sort of resilientstructure to furnish the required resistance. Several practical solutions of the problem have been provided. by the inventions of W. Lucas, (application Serial No. 514,722, filed Nov. 12, 1921), and Gr. C. Thomas (application Serial No. 516,19511', filed Nov. .18, 1921 which provide a resilient hinge, anchor, or abutment pin arranged to receivea bend ng stress as the collapsing IDOYBIIRQII'D bQgHIS, thus offering a resilient and increasing esistance to such movement. Thepresentinvention has for an llIiPOl'ttLllll'ObjQCl; still further. to simplify and improve constructions embodying this principle.

Accordingly, inaccordance with an important feature of the invention, the illustrated collapsiblelast has a pin for the purpose described,supportedyby terminal en.

larged portions shown as bushings at its ends in a hole of a diameter substantially largerithan its unenlarged middle portion, a

the oversize holeprovidingspace for it'to bend when deformed bythe stresses incidental to collapse.

These andother features of the invention,

including certain details of construction and combinations of parts. will be best understood from the following description of a preferred, embodiment selected for purposes of illustration and shown in the accompanying drawings, in which Fig. 1. is a side elevation of a last eiiibodylllg' the invention, partly broken away to show the mechanism. 7

Fig. 2 shows the last of Fig. l collapsed.

Fig. Fig. 1. t

The last shown consists of a heel part 10. a forepart 12 and a bonding member 14 linl ing them together. The heel partand forepart are separated by a cut of such shape as to permit them to turn relatively to each other.. In the last illustrated the out comprises a V-shaped opening 16 at the top of the last, a circular knuckle 18 on one part bearing in the other, and a straight 3 is a section on the line 3-3 oi portion 20 extending from the knuckle to the bottom of the last. The link 14 is anchoredin the last parts by pins 22, 24, passing transversely through the last parts. hese pins are herein shown as cylindrical throughout and are mounted in holes 26 considerably larger than themselves, and are supported by bushings 28 at their ends which tightly fill the holes 26. The hushings may be tapered to facilitate driving them inwvhen the lastis assembled toovercome the stress imposed on the pins by the linkllinthe assembling of thelast in order to hold the last parts firmly together innormal position.

, The line 30 joining the centers of the pins 22, 24 passes below the center 32 of the knuckle 18, when the. last is in extended position, as shownin Fig. 1. As the heel parts rises in the collapsingmovement, this line rises toward the center 32, and may pass it. As it approaches the center 32 the pins bend still further from the initial contour imposed on them in assembling the last, as SliOWli in 3 in dotted lines, since the ei'lectivelength of the link 14: is substantially less than the sum. of the distances" from the center to its (effective) ends, during the first-part ot the collapsing ii'ioveinent. I

The large holes/26 provide spaces in the last into which the pins have room to bend. Thelinkl l may be made Wide as shown, in or der to support the last parts against twisting stresses.

The resil ency of the pins provides an initial definite and increasing I'GSlSi H DCEBiU collapse, and thus the structure illustrated constitutes an impositivc lock for the last. If the line 30 passes above the center 32 in collapse the last will be iiiipnsitivcly locked in collapsed position also.

One of the pins may fully fill its hole. as in ordinary last C(lllSl'lllCtlOI], leaving; the

other to perform all the functions of the Y In order to keep the parts tight at all times the angle 16 of the cut in the last should not be much greater than the angle 42 between the intersections of the arcs 38, 4-0, measured at the pivotal center 32.

Having described my invention, what I claim as new and desire to secure by Letters Patent or" the United States is:

1. In a last, a heel part, and a forepart arranged for relative collapsing movement, a pin arranged during collapse to receive stress from one lastpart at its ends and from the other lastpart at its central portion, the pin having bushings at its ends supporting its central portion out of contact With the last parts.

2. In a last, a hinge pin of substantially uniform cross-section, the last having a hole substantially larger than the pin with bushings supporting the ends of the pin in the hole,and a member arranged to deform the pin transversely at its middle part to a substantial degree during the collapse of the last.

3. In a last, a heel part and a forepart, arranged for relative collapsing movement, a link connecting them, a pin mounted in each last part, said link being mounted at its ends on said pins respectively and said link and pins being constructed and arranged to hold the last parts firmly together, and one of said last parts having a hole of greater diameter than that of the pin mounted therein, the pin being bushed at its ends to support it in said hole.

41. In a last, a heel part and a forepart, arranged for relative collapsing movement, a link connecting them, a pin mounted in each last part, said link being mounted at its ends on said pins respectively and said link and pins being constructed and arranged to hold the last parts firmly together, and one of said last parts having a hole of greater diameter than that of the pin mounted therein, the pin being hushed at its ends to support it in said hole, said link and last parts being constructed and arranged to deform the pin by a pull on the link as the last collapses.

5. In a last, a forepart, a heel part arranged toturn relatively about a center to collapse the last, a link joining them with its eti'ective length lying below said center when the last is extended, one of said last parts having a hole, and a pin mounted in said hole and passing through an end of said link, said pin being substantially smaller than the hole, and having bushings at its ends to support it in the hole.

6. A last comprising a heel part and a forepart arranged to rotate relatively to offeet collapse of the last, a link joining the last parts, the efi'ective length of the link being less than the sum of the distances of its ends from the center of rotation, and said effective length lying below the said center when the last is extended, a resilient pin connecting one end of the link to its last part, arranged to bend under the stress of collapse, the said last part having a hole in which the pin is mounted, said hole being substantially larger than the pin to provide room for bending, and bushings in the hole supporting the ends of the pin.

7. A hinged last comprising a forepart and a heel part capable of movement between an extended position and a collapsed position, a bonding member connecting them constructed and arranged to permit them to move from one of said positions to the other, and a resiliently distortable pin arranged resiliently to resist such movement and to cooperate with the bonding member to hold the last in extended or collapsed position, said pin having a cylindrical middle portion and enlarged end portions and the last having a hole in which said pin is mounted which hole is substantially larger than the middle portion of the pin to permit distortion of the pin at the middle portion.

In testimony whereof I have signed my name to this specification.

\VALTER W. SLACK. 

